Brake



06L 5, 1937. cAMPBELL 2,095,026

BRAKE Filed Jan. 16, 1937 2 Sheets-Sheet l ATTOR N EY Patented Oct. 5, 1937 I UNITED STATES ATENT OFFICE,

BRAKE Bruce H. Campbell, Atlanta, Ga.

Application January 16, 1937, Serial No. 120,997

4 I 2 Claims. (01. 18830) This invention relates to automatic or safety tangentially to the periphery of thebr'ake shoe. brakes for motor vehicles and has for the primary The forked portions permit the brake shoe to object the provision of a'device of this character expand and contract. Opposite to the ends 8 of which may be readily adapted to a motor vehicle the split brake shoe a bracket I2 is secured thereor its drive shaft to prevent the vehicle from movto and said bracket is yieldably connected to the 5 ing rearwardly on a grade or hill when brought frame 5, as shown at E3. The bracket l2 coopto a stop and prior to again starting forward and erates with the forked portions in movably supwhich will automatically permit the vehicle to porting the brake shoe in relation to the brake proceed forward when power is applied to the drum. Substantially U-shaped guide elements l4 l0 drive shaft from the engine of the vehicle, the are secured to the brake shoe and act to retain 1O device having means for rendering the same opthe brake shoe in proper alignment with the erative and inoperative as desired. brake drum. The guides terminate at opposite With these and other objects in view, this insides of the brake drum and out of the path 0 vention consists in certain novel features of conmovement of the pins 4.

struction, combination and arrangement of parts Adjacent one of the ends 8 of the brake shoe a 15 to be hereinafter more fully described and journal I5 is provided. The journal supports a claimed. dog It of substantially U-shape. The dog being For a complete understanding of my invention, of the shape described straddles the drum and reference is to be had to the following description has connected thereto a coil spring [1 acting to and accompanying drawings, in which position the ends of the dog in the path of the 20 Figure l is a fragmentary plan View showing pins 4. An arm I3 is formed on the dog and a part of a motor vehicle with a brake applied abuts with a stop l9 under the action of the thereto and constructed in accordance with my spring ll. Connected to the arm [8 is a flexible invention. element 2!] extending to a place upon the motor Figure 2 is a sectional view taken on the line Vehicle which will be in convenient reach of the 25 22 of Figure 1. operator and may have connected thereto a suit- Figure 3 is a sectional view taken on the line able control (not shown), which when in one 3-3 of Figure 2. position will hold the dog out of the path of the Figure 4 is a detail sectional view taken on the pins and when released from said position will line 4-4 of Figure 2. permit the spring I! to move the dog into the 30 Figure 5 is a fragmentary transverse sectional path of the pins. view showing the brake rendered inoperative. The drive shaft 2 rotates in the direction of Figure 6 is a sectional View taken on the line the arrow in Figures 2 and 5 when the Vehicle is 66 of Figure 5. in reverse motion.

Figure 7 is a fragmentary vertical sectional In operation, when the driver of the vehicle 35 view showing a modified form of my invention. brings the latter to a stop on a hill or grade the Referring in detail to the drawings, the nucontrol cable 20 is actuated permitting the dog meral I indicates a fragmentary portion of a to assume the position as shown in Figure 2, that chassis of a motor vehicle and 2 the drive shaft, is, in the path of the pins 4 so that should the the latter having secured thereon a brake drum vehicle start to move in a reverse direction down- 40 3 provided upon opposite faces thereof with relahill or grade the dog will be engaged by a pair tively spaced pins 4. of the pins and thereby prevent the drive shaft Mounted on the chassis I is a supporting frame from rotating in the direction indicated by the 5 of skeleton formation including pairs of upper arrow in Figure 2. However, as soon as power and lower horizontally arranged bars 6 for supis applied to the drive shaft 2 to bring about for- 45 porting a brake shoe 1 in proper relation to the ward motion of the vehicle, the dog may ratchet periphery of the drum. The brake shoe is of the relative to the pins. After the vehicle has prosplit type, the ends being indicated by the charceeded from the hill, the operator may by actuacter 8 and are apertured to receive a bolt 9 ating the control position the dog as shown in having thereon a coil spring I0 acting against the Figure 5 so that the dog will be out of the path ends of the brake shoe for expanding the latter of the pins. When pins of the drum engage the away from the periphery of the drum. Forked dog during the rotation of the drive shaft in the portions l l are formed integrally with the brake direction indicated by the arrows in Figures 2 and shoe and slidably receive the supporting rods 6 5 the brake shoe will be caused to contract and of the frame 5. The forked portions ll extend grip the periphery of the drum, consequently pre- 55 ,ventinglthe vehicleffrom 'm g a: revrse direction." 7

"a sup rt for the brake shoe.

Having described the invention, I claim: .i

1. A brake icomprising a drum isecuredc'toafl dri vejshaft of; a motor vehicle, a 'splitshoe' Si1I rounding thefdrum,-spring;means acting to ex pandjtheffshoeawayfrom the drum,"iorked;por-

"tions formedaon the sho'e and extending tangen- 1 iel y her tm,a' i bnqr em ans including b rs" ec i d hvme o ked por n'sgga yieldablercone V T *2,o95,o26 7 7 V i nection "between the shoe arid the supportihg means, and a manually controlled ratchet means 1 The brake s hoe-isequipped with a brake lining,

between the shoe and;druin tobring about con drive shaft of a motor vehicle, a split shoe surtions formed on the-shoe and extending tangen-' tially thereto, a supporting means including bars received by the forked portions, a. yieldable con- .nection between, the shoe and the: supporting 'means, pins secured to' the drum, a spring actuated dog carried by the shoe andnorrnally posi tioned in the path ofthe; pins to bring about contraction of" the shoe against the drurnflby'the rotation ofgthedrive shaft infa reverse direction; and a control meansconnectdto the dogwhereby be positionedout 0f the' path' orthe latter may saidpins. i H

traction of the shoe on the drumlby rotation of g 7 the drive'shaftin a reversedirection, V 72; A brak e comprising a drum 'securedto a rounding theidrum, spring 'rnea'n's acting to. ex- 7 panel the shoe away from the drum, forked por- LBRUCE HQCAMPBEL Q V 

